Sadie the scientist has been studying a sedimentary rock layer. Her recordings can be seen in the diagram below:

Question

Sadie is surprised to see that only the bottom layer has fish fossils that appear. Why has there been a shift from fish fossils to cactus fossils in the sedimentary rock layer? Choose 2 options from the list below that support Sadie's research.

(1 point)
Responses

Layer C formed at a time when the area was an aquatic environment.
Layer C formed at a time when the area was an aquatic environment.

The sedimentary rock layer is disturbed.
The sedimentary rock layer is disturbed.

The fish population is extinct in the United States.
The fish population is extinct in the United States.

The environment conditions have changed over time.
The environment conditions have changed over time.
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Answer 1

To support Sadie's research regarding the shift from fish fossils to cactus fossils in the sedimentary rock layer, the two options that make the most sense are:

1. Layer C formed at a time when the area was an aquatic environment.
2. The environment conditions have changed over time.

These options imply that the appearance of fish fossils in the lower layer indicates an aquatic environment, while the presence of cactus fossils in the upper layers suggests a shift to a more terrestrial or arid environment over time.